1. Field of the Invention
The present invention relates generally to ink cartridges configured to be used in an image recording apparatus, and methods of manufacturing such ink cartridges. More specifically, the present invention relates to ink cartridges comprising an elastic member and a cap surrounding the elastic member, and methods of manufacturing such ink cartridges.
2. Description of Related Art
A known ink-jet image recording apparatus has a recording head and an ink supply device configured to supply ink to the recording head. A known ink cartridge is configured to be mounted to the ink supply device. The known ink cartridge has a case, and the case has an ink chamber formed therein. The ink chamber is configured to store ink therein. The case has an ink supply portion, and ink is supplied from an interior of the ink chamber to an exterior of the ink chamber via the ink supply portion. When the known ink cartridge is mounted to the ink supply device, ink stored in the ink chamber is supplied to the recording head via the ink supply portion. The recording head is configured to selectively eject ink toward a sheet of paper, such that an image is recorded on the sheet.
Another known ink cartridge, such as the ink cartridge described in JP-A-2007-144808, has an ink supply portion having a tube-shaped wall extending from a particular face of a case of the ink cartridge. The another known ink cartridge also has an elastic member positioned at the end of the tube-shaped wall. The elastic member has an opening formed therein. When the another known ink cartridge is mounted to the ink supply device, an ink tube of the ink supply device is inserted into the opening of the elastic member. When this occurs, the elastic member elastically deforms and contacts the outer surface of the ink tube liquid-tightly. The another known ink cartridge also has a cap, and the elastic member is sandwiched between the end of the tube-shaped wall and the cap while the elastic member is elastically deformed. The cap has an end wall having an opening formed therein, and a peripheral wall covering a portion of the elastic member and a portion of the tube-shaped wall. When the another known ink cartridge is mounted to the ink supply device, the ink tube is inserted into the opening of the cap and then into the opening of the elastic member. The another known ink cartridge has protrusions extending from the outer surface of the tube-shape wall in radial directions of tube-shaped wall. The peripheral wall of the cap has openings formed therethrough. The protrusions of the ink cartridge are fitted in the openings of the peripheral wall of the cap, respectively, such that the cap is attached to the tube-shaped wall. The peripheral wall of the cap also has slits formed therethrough, and the slits extend in the axial direction of the tube-shaped wall. Because the protrusions extend in the radial directions of tube-shaped wall, the peripheral wall of the cap deforms, such that the diameter thereof increases in the radial directions of tube-shaped wall during the process of attaching the cap to the tube-shaped wall.
Nevertheless, the elastic member may be elastically deformed while being sandwiched between the end of the tube-shaped wall and the cap, such that a portion of the elastic member moves into the openings of the peripheral wall of the cap. Consequently, the elastic member may be deformed unevenly. When the ink tube is inserted into the opening of the elastic member, the contact between the elastic member and the outer surface of the ink tube may not be liquid-tight because of the uneven deformation of the elastic member. In such a case, ink may leak between the elastic member and the ink tube. Moreover, the cap may deform unevenly during the process of attaching the cap to the tube-shaped wall because of the slit formed in the peripheral wall of the cap. This also may cause the uneven deformation of the elastic member.